Variable speed transmission



Cd. 22, 1940. c B- LENNEY 2,218,551

I VARIABLE'SPEED TRANSMISSION Filed May 28, 19440 2 Sheets-Sheet l Oct.22, 1940. c. B. LENNEY I VARIABLE SPEED TRANSMISSION Filed May 28, 19402 Sheets-Sheet 2 Patented Oct. 22, 1940 UNITED STATE s PAT OFFICE{VARIABLE SPEED TRANSMISSION I Clarence BJLenney, Warren, Ohio vApplication May 28,1940; Serial No. 337,621 s o 12 oiaims. (01. 74-194 Ih This invention-relates toa'p'o r transmission device and moreparticularly to aLtransmission in'whi'chthe ratio of speedbetweenthedriving and the drivenfshaits may be infinitely varied at 5 will;Thetrari'smission'is of the-friction type and the invention includesimprovements in the mechanical elements a and arrangement whereby thedriving forces are'transrn'itted through the frictional unit withoutslippage and without ex- 10 cessi've wear o'f any part. Animportantobject of theinvention is the 'simplification of theoperativeelements of thetra'nsmission and of the arrangement of'such'elements in order to 'reduce the cost of production of the mechanism, 15to render the same more durable and rugged in use, and to eliminate allvibration and chattering there'n whereby the usefulness of the assemblyis materially enhanced.

Another object of the invention is to provide 20 a transmission of thevariable speedtype having the characteristics indicated above which willoperate equally well in both directions and in which the speed rationiay'bevaried either while running or at rest f 25 Still another objectof 1 the invention is' 'to provide an infinitely variable speedtransmission which-*is' compact in design; in which the driving anddriven shafts-are axially aligned and which may; be'readi'ly"constructedin an economical 30 m I v U The design of the transmission read'ilylends itself to combination witha motorand'my inv e tjion' also includesa' novel variable speed power unit in which a "motor is combined wit 5the'transmission in a novel inannen i V The present application'isa-continuation in part of the applicants prior application Serial Number193,785, filed March 3, 1938.

These 'and other objects and "advantages of 50 Figure 3 is anenlargedsectional view of a portion of the apparatus constituting theinvention, the view being taken along the line III-III of Figure 1'. p tl The preferred embodiment of the invention,

55 asiillustrated inthe above described drawings,

the invention Will become apparent from a'conincludes acylindricallyshapedcenter housing section I having inwardly directedflanges l lat the ends thereof to whichis secured in any suitablemariner the end casing sections I2 and I3, respectively, each of whichis adapted to rotat 5 ably support one oithe'outer connecting shafts ofthe mechanism. For example, the end casing section 12, being secured'tothe casing section "I by the cap'screws l4, isadapted'to rotatablysupport the driving shaft 15 which is provided with an enlarge'd'endsocketed innerend I6. Two widely spaced antif riction hearings supporttheshaft'in'th section Hand the smaller of these bearings, designated byreference numeral 11, t is mounted adjacent the outer end of the memberI2 and carries a radial load only. The larger of the antifrictionbearings, designated I8, is mounted at theinner end of the member l2and. about 'the' en'larged innerend? I'G of'the shaft l5 and is adaptedtocai'ry both'radial and thrust Within the fiiiish edsocke t oftheshaftI5 is fitted an elongated'needle roller bearing ;l9 to receive the"hardened" and ground hub 20 of a driving""d'isk 2|. :iThe drivingdisk'is free to rotateirrthe' socket of theshaft l5 a verysensitive"manner. 'Ex'teriding diametrically throughthe'shaft '15 at the'base of.the'socket therein is a bore'adapted totightly receive ahardened'and'groun'd 'pin 22; The centeroof the pin' and the boreJ'is'byond" the inner end of the socket" but a portion'of the peripheryof the pin extends into the socket as, shown in Figure 1. The end' of"the hubZfl is provided with a shallow transverselyextending groove 23,the

outer surface of which is adapted to be in cotact"With'the.:outer'peripherybf the pin 22. It shouldbe" apparent thatupon' any relative rotatio'n between'th'e'driving'disk 2 i and thedriving shaft"l5',\ thedisk'will move in a direction out- 40 wardly'offth'e'socket with respectto the socket andshaft" byreaso'n' of theca'maction between th'e'pin22'and"groove 23. iHub 20 is provided with alarge longitudinal bore 24, as 'shown, to provideproperdubri'cation,of'the various wearing-sur'faces withirr the socket;

""Extendi-ng transversely o-f-the axis of rotation of *the drivingshaf-tyand disk is a heavy shaft-25; one end -of;which'is journaled inan antifriction bearing26- suitably mounted in the wall of; the casingsection in Theother end of the shaft 25 ,is jou rna1ed in anantifriction bearing; 21 which in turn is mounted in a steel slidingblock IQ-mounted for l irnited horizo-ntal I sliding mo vement in avvindow- Zg infthe wall of to take .both radial and thrustloads.

the casing section If) diametrically opposite the first mentioned end ofthe shaft 25. See Figure '3. Block 23 is suitably retained in positionaxially of the shaft 25 by the cover plate which is detachably securedto the casing sectian ID by the cap screws 3|.

A hardened steel roller 32 is feathered on shaft 25 toward the' endthereof which is carried by the block 28. The outer periphery of theroller 32 is adapted to be maintained in pressure contact with theground plane face of the driving disk 2!. Roller 32 is arranged to bemoved longitudinally along shaft 25 by a mem: ber having downwardlyextending forks 35 to engage opposite faces of the roller 32. Mem-v ber35 is moved in a path parallel with the axis of rotation of the shaft 25by a screw 31 threadedly received in a threaded vbore through;

held from axial movement by the bearings 33 and 39 in thecasingsectionlli and is adapted to be rotated by a hand wheel 40. Itshould be obvious, however, that screw 3'! may be rotated by a motor,remote control or other automatic means, if desired. l

The position of the roller .32 axiallyof the shaft 25 determines thespeed ratio between the driving and driven shafts of the mechanism andto indicate the position of the roller 32 so as to indicate the speedratio at which the mechanism is running, an indicator dial 4|, suitablyhoused in a protective cover 42, is mounted on top of casing sectionIII. 1 Dial 4| is keyed to a shaft 43 havinga pinion gear 44 keyed toits lower end and the pinion gear 44 meshes with a rack gear 45 suitablyfastened to the upper surface of the roller moving member 35.

Keyed to the shaft25 adjacent to but spaced from the block28 isa beveledroller, 41, the peripheral surface of which is hardened and ground. Thisroller is adapted to contact the hardened and ground beveled ring face48 of the driven disk 49. The latter is provided with a hollow groundand hardened hub 55, identical with the hub 20 of the driving disk. 2|,and the end-0f the hub 50 is provided with. a transversely extendingshallow groove 5|, identical with the first-described groove 23. Hub 5!!is journaled in needle roller bearings 52- which in turn are fittedwithin 3 the socket of the enlarged inner end 53 of the driven shaft'54." Shaft 54 is rotatably supported by the end casingsection [3 whichis detachably secured to the casing section H] by the cap screws 55, forexample, and for the purpose of so mounting the shaft. 54 anantifriction bearing 56 is provided adjacent the. outer end of themember 13 to take radial loads, while=an enlarged antifriction bearing.51 rotatably supports the enlarged inner end of the shaft 54 and isarranged A transversely extending hardened and'ground steel pin 58 ismounted in the shaft 54 to engage groove 5!, the arrangement beingsimilar in all respects to the torque loading arrangement described forthe driving'end of the transmission. Y

The operation of the'mechanism thus far described should now be readilyunderstood. If rotative power is supplied to shaft 15 and resistance torotation isencountered by shaft 54, the

i curved surfaces 23=and5l instantly act to tighten The grooves 23 and5| are of sufficient depth to insure the transmission of the rotationfrom shaft IE to disk 2! and from disk 49 to shaft 54. By floatinglymounting the roller end of the transverse shaft 25, thereby allowingsaid end to be moved a short distance sideways, any rotative impulseapplied to the shaft 15 is immediately operative to apply pressurebetween the bevel surfaces 41 and 48 as well as between disk 2| androller 32.

Consequently, disk 49 assumes rotation with the rotation of shaft l5.

The transmission is intended to operate in a bath of oil and for thispurpose the casing made up of the sections I0, 12 and I3 is made oiltight and is provided with suitable means, not shown, whereby oil may besupplied to and drawn from the casing. All bearing and wearing surfacesare continuously and adequately lubricated. Since every moving part ofthe apparatus is in dynamic balance, no vibration of any kind isinherent inthe operation of the apparatus and by, eliminating thenecessity for any gears whatsoever the apparatusis very quiet inoperation. The symmetry. of-the grooves 23 and 5! enables thetransmission.to operate in either direction With equal results andefi'iciency.

The high pressures employed between the driving disk 2| and the rcller32 in the normal operation of the transmission results infconsiderableheating taking place on the peripheral surface of the roller andit hasbeen found desirable to employ a heat resisting tool steel in theconstructionof this element. Inasmuch as the wearing surface ofthedriving disk is distributed over a wide area, no excessive localheating takes place on this member. All the bearing and wearing surfacesare cooled by the oil bath which tends to equalize the temperaturethroughout the unit and the radiation and conduction of heat from theunit generally has been found sufficient to prevent undueheating of thesame.

While obviously steels of various compositions may be used for thefriction-elements, depending on cost and service considerations, I havefound that steel consisting of 2.19% carbon, 25% manganese, 25% silicon,12.50% chromium, 50% nickel, balance iron, properly heat treated, iswell suited for the disk and steel consisting of .70% carbon, 35%manganese, .20% silicon, 3.75% chromium, 18.50% tungsten, 1.10%vanadium, balance iron, properly heat treated, is well suited for theroller. Carbon and chromiumadd hardness andtoughness to the disk and thetungsten in the rollerlends heat resisting qualities thereto. It is alsothought that the use of dissimilar metals increases the coefiicient offriction between the elements. 7

The design of s the applicantsapparatus is such that one'of the shafts,astheshaft l5, may be integrally extended, as shown in Figure 1 of thedrawings, to receive a rotor of an electric motor. For this purpose theextended end of the shaft is tapered and a tapered sleeve BI ispositioned over the shaftand within the bore of the rotor and theassembly; is wedged up tight and held in tightened' position by a nut 62threaded on theouter end of the shaft. An air impeller 63 may also beattached to the shaft 15 outwardly of the. .rotor 60. Thestator 64 ofthe motor is secured within housing65 which is adapted to be secured tothecenter casing section ID by the cap'screws l4 and when the parts areso assembled the stator is in proper position relativeto-the motor. Itshould be observed that no additional bearings or shafts are requiredfor the motor and that *only anadditional housing member is required.The combined unit is compact in design, quiet and efficient in operaticand is well suited for a wide variety of uses;

It should now be apparent that the inventio provides an apparatus whichfully. accomplishes the'objects initially set out. The elimination ofall tooth gearing substantially reduces the cost of producing thetransmissions, eliminates vibration and chattering and results inveryquiet operation of the assembly. By carrying the transverse shaft,25. and the attendantroller moving and position indicating assemblyentirely by the center casing section'lfl and by rotatablysupporting'the driving and driven'shafts and disks entirely by therespective end casing sec-. tions, the assembly and servicing. of .themech-, anism is greatly facilitated. v

The above specifically described embodiment of .the invention should beconsidered as illustrative spaced axially aligned bearings in'said endmemcomprising a casing having end members and an bers, a memberpositioned within said casing and carried by and rotatable withone ofsaid shafts, a face plate rotatably carried by theinner end of the saidone of said shafts, a third shaft rotatably carried by said intermediatesection and extending transversely of said first mentioned shaft,

a roller keyed tosaid third shaft and adapted to be maintained inpressure contact with said face plate, said. pressure being maintainedby means positioned between said rotatable member and said face plateand adapted to move said-face plate and said member away from each otherupon relative rotation thereof, meansto move said roll--w er axiallyalong said third shaft, and means to transmit rotary motion from saidthird shaft to the other of the shafts journaled in said end members.

2. A variable speed power transmission device intermediate section,shafts carried by and journaled intermediate their ends in spacedaxially aligned bearings in said end members, a member positioned withinsaid casing and secured to one of said shafts at a point spaced from itsinner end, a face plate rotatably carried by the inner end of the saidone of said shafts, a third shaft journaled in said intermediate sectionand extending transversely of the said one of said shafts, a rollerkeyed to said third shaft and adapted to be maintained in pressurecontact with said face plate, said pressure being maintained by meanspositioned between said member and said face plate and adapted to movesaid member and said face plate apart upon relative rotation thereof,means to transmit rotary motion from said third shaft to the other ofthe shafts journaled in said end members, a screw journaled and axiallyfixed in said intermediate section, a member having screw threadedconnection with said screw adapted to confine the axial position of saidroller, a rack carried by said last mentioned member, a shaft journaledin said intermediate section and having an attached pinion meshing withsaid rack, and an indicator keyed to said last mention-ed shaft outsideof said intermediate section.

3, A variable speed power transmission device comprising in combinationa casing having end members and an:intermediate section,shafts'carriedby and journ'ald intermediate :the ends in spaced axiallyaligned bearings in said endmembers, one of the'bearings in each of saidend members-being capable of opposing both axial and thrust'loads,the'inner end of one of said shafts being provided with an' axiallyopening socket, a cam surface'in the bottomwall of said socket, a faceplate having an attached hub rotatably received within said socket, theinner" end of said relativerotation between the said one of said shaftsand said face plate will result in said hub and face plate being movedin a direction outwardly of .said socket, a third shaft rotatably car-'ried by said intermediate section and extending; transversely of saidfirst mentioned shaft, a roller.

keyed to said third shaft adapted to contact said faceplate, means tomove said roller axially along said third shaft, and means to transmitrotary motion from said-third shaft to the other of theshaftsjournaledflin said end members.

4, Apparatus according to claim 1 in'which said last mentioned meansincludes a frusto-conical roller keyed on said third shaft, afrusto-conical' ring carried by said other of the shafts, andv means tomaintain the interengaging surfaces of the last mentioned roller and thering in pressure contact. i r j 5. Apparatusaccording to claiml in whichsaid last mentioned means comprises a roller having a frusto-conicalsurfacekeyed on said third shaft, a memberconnected with the said otherof the shafts andhaving a frusto-conical surface adapted to engage saidfirst mentioned conical surface, oneend of said third shaft beingfloatingly mounted whereby pressure may be applied through said faceplate, first mentioned roller, shaft and second mentioned roller to saidlast mentioned interengaging surface.

6 A variable speed transmission comprising in combination a casing, ashaft journaled intermediate its ends in one wall of said casing, saidshaft being provided with an axially socketed inner end, a cam surfaceon the bottom wall of said socket, a face plate having an attached hubrotatably received in said socket, the inner end of said hub beingprovided with a cam surface to engage the first mentioned cam surfacewhereby said hub will hubsbeing provided with a cam surface whereby bemoved outwardly of said socket upon relative rotation of said shaft andface plate, a second shaft extending transversely of said first shaftand beyond the outer face of said face plate, a roller feathered on saidsecond shaft and adapted to be maintained in pressure contact with theouter face of said face plate.

'7. Apparatus according to claim 6 further including a third shaftjournaled in a wall of said casing, and means to transmit rotary motionfrom said second shaft to said third shaft comprising a second rollerkeyed on said second shaft, a cooperating roller keyed on said thirdshaft, said second shaft being floatingly mounted whereby pressure maybe applied through said face plate, first roller and second shaft to theinterengaging surfaces of the second and third roller.

8. A variable speed transmission comprising in combination a casing, ashaft journaled intermediate its ends in a sidewall of said casing, theinner end of said shaft being provided with an. axially extendingsocket, a bore extending transversely of said shaft with its centeradjacent the bottom wall of said socket, a pin secured in said bore andhaving a portion of its peripheral surface extending into said socket, aface plate having an attached hub rotatably received in=said socket, theinner end of said hub having a shallow. transverse groove adapted torbereceivedabout the surface of thepin in the socket whereby said shaft andfaceplate will be moved apart upon relative rotation thereof, a secondshaft extending transverselyvof saidfirst mentioned shaft, 2.rollerfeathered on said second shaft and adapted to be maintained inpressure contact with the outer face of said face plate, and means tomove said roller axially along said second mentioned shaft.

9. A variable speed transmission comprising in combination axiallyaligned shafts, antifriction means to rotatably support said shafts andto prevent outward axial movement thereof, the inner ends of said shaftsbeing each provided with axially extending sockets, cam surfaces in thebottom walls of each of said sockets, a face plate having a hubrotatably received in one of said sockets, a member having an annularsmooth surface rotatably received in the other of said sockets, the.outer endsof each of said hubs being provided with a cam surface toengage said first mentioned cam surfaces, a fioatingly mountedshaftextending transversely of said first mentioned shafts andintermediate said face plate and member, a roller feathered on saidtransverse shaft and adapted to engage said face plate, and a secondroller keyed on said transverse shaft and adapted to engage said annularsurface.

10. A variable speed transmission comprising in combination a pair ofspaced axially aligned shafts, antifriction bearings to rotatablysupport said shafts and to prevent outward axial movement thereof, aface plate rotatably mounted on the inner end of one of said shafts, atorque loading means between said face plate-and the said one of saidshafts, a member rotatably supported on the inner end of the other ofsaid shafts, torque loading means between said member and the other ofsaid shafts, an annularsurface on said member, concentricwithithe axisofrotation of said shafts, a transverse shaft positioned between said faceplate and member, a roller feathered on said transverse shaft ,andadaptedto be maintained in pressure, contact with said face plate, and asecond rollerkeyed on said-transverse shaft and adapted to. bemaintainedin pressure contact with said annular surface.

11. Apparatus according. to claim 10 in which both said rollers arenormally positioned to one side of the :axis of rotation of the firstmentioned shafts, the. end-of said transverse shaft adjacent saidrollers being floatingly mounted.

12: A. variable, speed transmission comprising in-combination a casinghaving a center and two opposed end sections, a shaft journaled in eachof said end sections and restrained from radial and outward axialmovement, a face plate rotatably supported by the, inner end of one ofsaid shafts, a torque. loading means between said face plate and thesaid one of said shafts, a member rotatably carried by the inner end ofthe other of the shafts, a torque loading means interposed between saidmember and the said other of said shafts, an annular surface on saidmember concentric with the axis of rotation of said member and the saidother of sai'd shafts, a transverse shaft having one of its endsjournaled in a wall of said center casing section, the other end of saidtransverse shaft being journaled in a slide block, guide surfacescarried by said center casing section and adapted to receive said slideblock, said surfaces allowing sliding movement of said block toward andaway from either of said first mentionedshafts, a roller feathered onsaid transverse shaft and adapted to be maintained in pressure contactwith said face plate, and a second roller keyed on said transverse shaftand adapted to be maintained in pressure contact with said annularsurface, said rollers being normally mounted on the half portion of saidtransverse shaft adjacent said block.

CLARENCE B. LENNEY.

